The present disclosure generally relates to systems and methods to optimize respiratory exchange fat macro utilization metabolic profile.
Basal metabolic rate (BMR) refers to the energy (calories) required to maintain essential body functions and may account for 60 to 75% of daily total energy expenditure (TEE). BMR is in direct control of resting energy expenditure and ultimately determines whether an individual maintains, gains, or losses weight. Historical methods for estimating BMR have proven to be inaccurate with error rates ranging from 10 to 35%. Given that fact, the relative percentage of fat and carbohydrate constituting metabolic expenditure has been looked to as a more stable and reliable indicator of nutritional status. Fat and carbohydrate calories (commonly referred to as macronutrients) contribute independently to metabolic demand and that value is expressed as the Respiratory Exchange Ratio (RER) and is most often derived from laboratory indirect calorimetry metabolic testing, wherein oxygen and carbon dioxide gases from inspiration and expiration are collected and measured as a function of heart rate from rest through anaerobic threshold. An RER value of 1.0 equals 100% carbohydrate energy utilization and an RER of 0.7 equals 100% fat energy utilization. Metabolic testing is a critical tool for the accurate measurement of individual metabolism in the medical, nutrition and fitness industries, yet it is expensive and has limited availability to the general population, and consequently, testing utility is not widely available. Also, calculating accurate BMR and energy expenditures associated with typical activities of daily living from indirect calorimetry is challenging as a result of hardware limitations. More accurate measurements require a complex sealed and airtight free-living laboratory setting (bomb or direct calorimetry) wherein all respiratory gasses are constantly measured over a 24-hour period and all sources of caloric intake are strictly measured. Ideally, an individual would have an RER value below 0.85 and approaching 0.7 at rest, during the course of routine activities, and with low intensity exercise, wherein fat is the optimal and primary energy source. However, the macronutrient composition of an individuals diet (relative fat % and carbohydrate %), and timing of meals is critical to determining whether an RER value is higher or lower at rest, or with low intensity activity. Low fat diets and frequent ingestion of carbohydrate are associated with a higher fasting and 24-hour glucose and consequently, a higher resting and low intensity activity RER. Alternatively, a high fat diet and relative periods of fasting greater than 2 hours, are associated with a lower fasting and 24-hour glucose and consequently, a lower resting and low intensity activity RER. Thus, increasing an individual's dietary fat macro utilization (FMU) will increase their resting fat use (RFU), and this is quantitated by a lower RER. Additionally, the diet and fitness industries have long desired to improve an individuals fat burning during exercise and have published target exercise heart rate zones for maximizing fat burning that are either 60 to 70% of an individuals maximum heart rate (estimated by the 220−age formula), or derived from the Karnoven method, wherein target heart rate equals ((maximum heart rate−resting heart rate)×% intensity)+resting heart rate. Unfortunately, neither of these methods is accurate, especially when compared to an individual's actual RER test (100% accurate) or the CORE FMU estimations (Root Mean Square Error beats per sec: Karnoven 33.83, Traditional 23.71, CORE FMU method 17.57).